What does 603 lb/ft at 3900 RPM feel like in a NSX? Really fast. And scary. And really addictive.
We recently completed a project for a customer in the Cayman Islands. This 1992 was shipped from Grand Cayman to Miami where it was then shipped from Miami to Phoenix for turbocharger and ScienceofSpeed 3.5L engine installation.
The project started out difficultly for the customer. Before contacting ScienceofSpeed, a turbocharger system was purchased and paid for in full from another company. After waiting nearly 2 years, the customer was left with 75% of a turbo system missing critical components, and a system that required nearly every component to be cut up, remade, and made to fit. After waiting this long, the customer decided to have ScienceofSpeed take on the project of correcting some glaring design and quality issues and to source and make the missing components. On a personal note, I've noticed that some of the nicest most pleasant NSX owners seem to be the ones that get taken the most. It's a shame to see - but I am relieved to see how happy the customer was with the outcome.
Working in conjunction with the turbocharger system is a ScienceofSpeed 3.5L engine. The factory 3.0L block was resleeved, billet main caps and main studs were installed, and the main bore was align bored & honed. The engine's rotating assembly consists of a balanced ScienceofSpeed 4340 billet crankshaft, 4340 billet connecting rods, and forged pistons increasing the bore from 90mm to 93mm and the stroke from 78mm to 86mm giving a total displacement of 3.5L. The cylinder heads were refreshed but left mostly stock.
The turbocharger system uses a Garret GT35R with a .82 AR exhaust housing. The single GT35R turbocharger was a little on the small side for the air volume this engine can pass, but yielded a very fast response with peak torque at 3900 RPM. A larger compressor would likely have yielded a higher horsepower number, but take a ride, and I think you'll find 600 wheel hp / 600 wheel tq in a 2900 lb vehicle is quite enough to dare and scare you to stay in the throttle till redline.
low boost, 91 octane
high boost, 110 octane
Completing this car, and from having completed other turbocharged NSX with the same Garrett turbocharger and low compression 3.0L engines, has given us a good chance to compare how the 3.0L engine compares to the 3.5L stroked engine. Despite using the same compressor, the 3.5L engine products 56 horsepower and 55 lb/ft more than the same compressor on a 3.0L engine with the same compression ratio, same cylinder heads, and the same fuel. All this, and at 2.5 psi LESS. The torque curve of the 3.5L engine, with the increased stroke, was also noticeably faster to respond (peak boost hit at about 300 RPM sooner and produced significantly more torque sooner in the RPM band.
3.0L (red) vs 3.5L (blue) wheel horsepower & torque (57 lb/ft & 55 hp increase):
3.0L (red) vs. 3.5L (blue) boost pressure (all at 2.5 less boost):
Thank you for the opportunity Philip, and have fun with your new toy.
Regards,
-- Chris & ScienceofSpeed Staff
We recently completed a project for a customer in the Cayman Islands. This 1992 was shipped from Grand Cayman to Miami where it was then shipped from Miami to Phoenix for turbocharger and ScienceofSpeed 3.5L engine installation.
The project started out difficultly for the customer. Before contacting ScienceofSpeed, a turbocharger system was purchased and paid for in full from another company. After waiting nearly 2 years, the customer was left with 75% of a turbo system missing critical components, and a system that required nearly every component to be cut up, remade, and made to fit. After waiting this long, the customer decided to have ScienceofSpeed take on the project of correcting some glaring design and quality issues and to source and make the missing components. On a personal note, I've noticed that some of the nicest most pleasant NSX owners seem to be the ones that get taken the most. It's a shame to see - but I am relieved to see how happy the customer was with the outcome.
Working in conjunction with the turbocharger system is a ScienceofSpeed 3.5L engine. The factory 3.0L block was resleeved, billet main caps and main studs were installed, and the main bore was align bored & honed. The engine's rotating assembly consists of a balanced ScienceofSpeed 4340 billet crankshaft, 4340 billet connecting rods, and forged pistons increasing the bore from 90mm to 93mm and the stroke from 78mm to 86mm giving a total displacement of 3.5L. The cylinder heads were refreshed but left mostly stock.
The turbocharger system uses a Garret GT35R with a .82 AR exhaust housing. The single GT35R turbocharger was a little on the small side for the air volume this engine can pass, but yielded a very fast response with peak torque at 3900 RPM. A larger compressor would likely have yielded a higher horsepower number, but take a ride, and I think you'll find 600 wheel hp / 600 wheel tq in a 2900 lb vehicle is quite enough to dare and scare you to stay in the throttle till redline.
low boost, 91 octane
high boost, 110 octane
Completing this car, and from having completed other turbocharged NSX with the same Garrett turbocharger and low compression 3.0L engines, has given us a good chance to compare how the 3.0L engine compares to the 3.5L stroked engine. Despite using the same compressor, the 3.5L engine products 56 horsepower and 55 lb/ft more than the same compressor on a 3.0L engine with the same compression ratio, same cylinder heads, and the same fuel. All this, and at 2.5 psi LESS. The torque curve of the 3.5L engine, with the increased stroke, was also noticeably faster to respond (peak boost hit at about 300 RPM sooner and produced significantly more torque sooner in the RPM band.
3.0L (red) vs 3.5L (blue) wheel horsepower & torque (57 lb/ft & 55 hp increase):
3.0L (red) vs. 3.5L (blue) boost pressure (all at 2.5 less boost):
Thank you for the opportunity Philip, and have fun with your new toy.
Regards,
-- Chris & ScienceofSpeed Staff
